Lift carrier

ABSTRACT

An improved lift carrier having a platform and a first means for lifting said platform under load and a quick-lift mechanism operative alternately in respect to said first means for raising the platform quickly when there is no load or only a light load.

United States Patent [1 1 [111 3,817,546 Sugiura June 18, 1974 LIFT CARRIER [56] References Cited [75] Inventor: Yoshikazu Sugiura, Aichi, Japan UNITED STATES PATENTS 73 Assigneez S i Kogyo Kabushiki Kaisha 3,567,240 3/1971 Brassington 280/43.l2

Takahama, Japan FOREIGN PATENTS OR APPLICATIONS [22] Filed: Mar. 9, 1972 516,114 12/!953 ltaly 280/43.12 Appl 233040 Primary ExaminerRobert R. Song [30] Foreign Application Priority Data 57 ABSTRACT Mar. l5, I971 Japan 46-17240 An improved carrier having a platfonn and a first means for lifting said platform under load and a quickg fg/ z lift mechanism operative alternately in respect to said n f t t k h [58] Field of Search 280/43.l2; 254/8 R, 8 c, first means ra'smg he pla form 1y when t ere is no load or only a light load.

13 Claims, 9 Drawing Figures LIFT CARRIER This invention relates to an improvement in or relating to the lift carrier in which the platform is raised or lowered by operating a jack, and which is convenient especially when there is no load or only a light load, if any, on the platform.

In the lift carrier known in the prior art, the platform attached to the plunger of the jack has been raised by operating a handle shaft. The handle shaft has been moved up and down as shown in FIG. 1 by a curved line having an arrow at each end thereof to operate a pump for lifting the jack and thereby raise the platform. But the handle shaft has had to be moved up and down many times to raise the platform to a predetermined height (H in FIG. 2). Such operation of the handle shaft has necessarily required extra time and labor. Such extra time and labor required for operating the handle shaft has been considered justifiable or unavoidable when the platform carries a relativelyheavy load, because the force required to lift the load has been considerably small as compared with the weight of the load carried on the platform. But such extra time and labor has likewise been required even when the platform carries no load or only a light load, if any. In this case, the extra time and labor required has been extra in the true sense of the word, and has been a great obstacle to the operation of the lift carrier.

It is, therefore, an object of this invention to provide an improved lift carrier which is provided with means for raising the platform quickly, and which can be loaded and unloaded very quickly, thereby the operating efficiency being increased to a considerable extent when there is no load or only a light load, if any, on the platform.

It is another object of this invention to provide an improved lift carrier which permits the platform to be quickly raised while the platform maintains a horizontal position.

It is still another object of this invention to provide an improved lift carrier in which a valve means is provided in the path of a fluid for operating a hydraulic jack, and is operated to allow the platform to quickly move down automatically from its raised position by its own weight and the weight of the load carried thereon, while maintaining a substantially horizontal position.

According to the present invention, a hydraulic jack is provided on a traction body. The upper end of a plunger of the hydraulic jack is connected with one end of the platform with a thrust bearing disposed in between. A quick-lift yoke having a substantially channelshaped section is loosely inserted over the plunger, and disposed between the upper end of the jack and the underside of said one end of the platform. The yoke is slidable upward and downward along the external surface of the jack. The lowermost portion of a handle shaft for operating the jack is engageable with an operating arm, and when the lowermost portion of the handle shaft is engaged with the operating arm and the handle shaft is pushed downward, the operating arm abuts against the lower edges of the side walls of the quick-lift yoke, and urges the yoke upward, and then, the yoke in turn raises said one end of the platform.

A preferred embodiment of the lift carrier according to this invention will now be described with reference to the accompanying drawings, in which:

FIGS. 1 and 2 are views schematically showing the side elevation of a preferred embodiment of this invention; FIG. 1 showing the platform of the lift carrier in its lowered position, while FIG. 2 shows it in its raised position;

FIG. 2a is a view showing the detail of a portion of the lift carrier below its traction body;

FIGS. 3-7 show details of various portions of the lift carrier according to this invention in their various operating positions; and

FIG. 8 is a cross-sectional view taken along line A-A of FIG. 7.

Referring to the drawings, a stay 3 is secured to the underside of a traction body 2 of a lift carrier according to this invention generally designated by the numeral 1. A wheel shaft 4 is secured to the lower end of the stay 3, and a large wheel 5 is rotatably carried by the shaft 4. A pedestal is inserted over the stay 3 adjacent to the upper end thereof with a bearing 56 positioned in between. A thrust bearing 57 is inserted over the upper end of the stay 3 and between the pedestal 55 and the traction body 2. The bearing 56 is closely fitted within the pedestal 55, so that the stay 3 is rotatable relative to the inner surface of the bearing 56. Mounted vertically on the traction body 2 are a jack 7 provided with an oil tank 6, and a pump 9 to supply oil 8 under pressure from the tank 6 to the jack 7. A quick-lift yoke 12 having a substantially channel-shaped cross section and a pair of depending sidewalls 11 is loosely disposed over the plunger 10 of the jack 7. The quick-lift yoke 12 is vertically slidable along guide plates 13 secured to the sides of the oil tank 6. The front end of a platform 15 having an off-set profile (the end of the platform shown on the left-hand side of FIG. 1) is pivotally carried on a thrust bearing 14 on the upper end of the plunger 10. A pair of brackets 16 are secured to the underside of the rear end portion (on the right-hand side in FIG. 1) of the platform 15. The corner portion of a substantially L-shaped arm 20 is pivotally carried on a pin 21 secured to the brackets 16. A small wheel 18 is rotatably carried on a shaft 17 attached to one end of the arm 20, and a pin 19 is attached to the other end of the arm 20. The corner portion of a substantially L- shaped arm 25 is pivotally carried on a pin 26 secured to the lower part of the front end of the platform 15. A slit 22 is provided adjacent to one end of the arm 25. A pin 23 secured to the side portion of the pedestal S5 is loosely engaged with the slit 22, and a pin 24 is attached to the other end of the arm 25. The pin 19 of the arm 20 and the pin 24 of the arm 25 are connected with each other by a rod 27, so that the arm 25 is pivotable counterclockwise with the upward movement of the plunger 10. (FIGS. 1 and 2) Each of the arms 20 and 25 has a length required to allow the small wheel 18 to maintain the platform 15 in a certain attitude, or in a substantially horizontal position according to the preferred embodiment of this invention as herein described, while the plunger 10 is being raised or lowered.

Brackets 28 are projected from the front side (the left-hand side in FIGS. 1 and 5), and have a pin 34 attached thereto. Carried pivotally on the pin 34 are the corner portion of an operating arm 32 having a substantially L-shaped vertical cross-section, and the righthand lower end portion (FIG. 5) of a handle shaft support 33 having a substantially channel-shaped horizontal crosssection. The operating arm 32 is provided at one end thereof with pins 29 on which rollers 30 are carried, and an engaging member 31 is secured to the other end of the arm 32. The rollers 30 are in contact with the lower edges of the side walls 11 of the quicklift yoke 12. A handle shaft 36 of hollow construction is secured to the handle shaft support 33, and has a grip portion secured to the free end of the handle shaft 36. The left-hand lower end portion (FIG. 6) of the handle shaft support 33 is provided with a pin 37, and a roller 38 is rotatably carried on the pin 37. The roller 38 is in contact with the upper end of an operating rod 39 for the pump 9. The operating rod 39 is pushed downward by the roller 38 to operate the pump 9 when the handle shaft 36 is moved from is raised position shown by solid lines in FIG. 1 down to its lowered position shown by broken lines. When the handle shaft 36 is moved from its lowered position up to its raised position, a compression spring 40 disposed between the operating rod 39 and the pump 9 expands to return the operating rod 39 to its original raised position (shown by solid lines in FIGS. 1, 4 and 7). A pin 43 is provided on the left-hand side of the handle shaft support 33 intermediate the upper and lower ends thereof (FIG. 6). Carried pivotally on the pin 43 is a locking member 42 having a substantially channel-shaped horizontal crosssection and formed at one end thereof with a groove 41. The groove 41 is adapted to be engaged with the engaging member 31 of the operating arm 32. A pin 44 is rotatably provided on one end of the locking member 42. The lower end of an operating rod 45 loosely inserted into the hollow portion of the handle shaft 36 is loosely inserted into the central portion of the pin 44, and is formed with a flange 45' to support the pin 44 thereon. An operating lever 46 is secured at one end thereof to the upper end of the operating rod 45. The other or free end of the lever 46 is projected substantially at right angles from the handle shaft 36. When the operating lever 46 is in its lowered position shown by solid lines in FIG. 3, the locking member 42 is disengaged from the engaging member 31 (FIG. 4), while the locking member 42 and the engaging member 31 are engaged with each other (FIG. 7) when the operating lever 46 is in its raised position shown by broken lines in FIG. 3. The operating rod 45 remains urged downward by a spring (not shown) at all times as shown by solid lines in Flg. 3.

A hydraulic valve operating member 47 is provided adjacent to the front lower end portion of the oil tank 6 for opening or closing a conventional valve (not shown) for the hydraulic circuit for the jack 7. A valve rod 48 is projected upward from the valve member 47, and is adapted to raise or lower the valve member 47 for opening or closing the valve operated by the latter. The valve rod 48 remains urged downward by a spring 49, and is connected at the upper end thereof with the lower end of the operating rod 45 by a chain 50 which is extended through a guide ring 51 protrudingly provided on the front upper portion of the oil tank 6. The member 47 is thus manually actuable via the operator moving said operating rod 45. A foot lever 53 is connected in substantially the middle portion thereof with the traction body 2 by a pin 54, and is pivotable about the pin 54. A pedal 52 is formed at the end of the lever 53 which projects beyond the front edge of the traction body 2. The other end of the lever 53 is engageable and disengageable in respect to said member 47 so that the latter is foot actuable via the operator moving said pedal 52. The hydraulic circuitry for the apparatus of the present invention is conventional and no claim is made herein to said circuitry.

Reference will now be made to the operation of the above described preferred embodiment of the lift carrier according to this invention. The hydraulic valve operated by the member 47 remains closed as long as both the operating lever 46 and the foot lever 53 remain inoperative as shown by solid lines in FIGS. 3 and 4. With the valve operated by the member 47 kept in its closed position, the movement of the handle shaft 36 upward and downward causes the operating rod 39 for the pump 9 to move up and down, whereby the oil 8 is sucked from the oil tank 6 into the pump 9 and then supplied under pressure to the jack 7. Consequently, the plunger 10 of the jack 7 is gradually raised by the force of the hydraulic oil supplied under pressure, and the platform 15 is also gradually raised together with the plunger 10 as the handle shaft 36 is moved up and down repeatedly. Thus, a heavy load carried on the platform 15 may be lifted by repeated operation of the handle shaft 36 (FIG. 2).

As the platform 15 is raised, the arm 25 attached to the platform 15 turns counterclockwise about the pin 26, so that the arm 20 carrying the small wheel 18 thereon is caused to turn clockwise about the pin 21. As a consequence, the platform 15 and the small wheel 18 are spaced from each other a distance approximately equal to the height by which the plunger 10 has been raised, and the platform 15 maintains a substantially horizontal position while it is being raised. To lower the platform 15 the operating lever 46 or the foot lever 53 is moved to a position shown by broken lines in FIG. 3 or a position shown in FIG. 6. The valve rod 48 is moved upward, and the hydraulic valve operated by the member 47 opened, so that the hydraulic oil 8 is returned from the jack 7 into the oil tank 6 by the weight of the platform 15, and the platform 15 is lowered. As the platform 15 is lowered, the arm 25, the rod 27 and the-arm 20 move in the directions opposite to those in which they move as the platform 15 is raised, so that the spacing between the platform 15 and the small wheel 18 is reduced by approximately the distance the plunger 10 has been lowered, and the platform 15 maintains a substantially horizontal position while it is being lowered (FIG. 1).

In order to raise the platform 15 to a predetermined height (the upper end of the travelling stroke of the plunger 10) by a single step of operation of the handle shaft 36 when the platform 15 carries no load or only a light load, if any, the handle shaft 36 is kept in its upright position (FIGS. 1 and 6), and the operating lever 46 is raised to the position shown by broken lines in FIG. 3 (FIG. 6). The locking member 42 is turned counterclockwise about the pin 43, and the groove 41 of the locking member 42 gets engaged with the engaging member 31 of the operating arm 32. Simultaneously, the chain 50 pulls the valve rod 48 upward, and causes the hydraulic valve operated by the member 47 to open. The handle shaft 36 is turned from its raised position to its lowered position (FIGS. 1 and 7). The operating arm 32 rotates about the pin 34 counterclockwise together with the handle shaft 36, and the rollers 30 provided on the operating arm 32 urge the quick-lift yoke 12 upward because they are in contact with the side walls 11 of the yoke 12. Accordingly, the plunger 10 of the jack 7 is raised together with the platform 15. When the handle shaft 36 is turned to its lowered position (FIGS. 1 and 7), the chain 50 is held inmovable by the guide ring 51, so that the position of the valve rod 48 makes no change, but the valve operated by the member 47 remains in its opened position. Therefore, the hydraulic oil 8 continues to be supplied from the oil tank 6 to the jack 7 as the pluger is raised. Moreover, as the platform is raised, the rod 27 transmits the rotative motion of the arm25 to the arm to thereby cause the arm 20 to turn clockwise, and the platform 15 maintains a substantially horizontal position while it is being raised.

The operating lever 46 is then brought back to its lowered position shown by solid lines in FIG. 3. The valve rod 48 moves downward, and closes the valve 47, so that the jack 7 is maintained in the position where its plunger 10 remains in its raised position. When the handle shaft 36 is brought back to its upright position (FIG. 2), the platform 15 is kept in its raised position (FIG. 2), while the operating arm 32 and the quick-lift yoke 12 return to their respective original positions. The platform 15 may be lowered by opening the valve operated by the member 47 by either raising the operating lever 46 to its raised position shown by broken lines in FIG. 3 or treading on the foot lever 53 as shown in FIG. 6. Thus it can be seen that the valve operated by the member 47 is in a by-pass relationship with the pump 9, i.e., when closed, it prevents flow of oil between the jack 7 and the tank 6 to hold the platform 15 in any of its elevated positions and with interfering with operation of the pump 9 in raising the platform 15 with a load thereon. When the valve operated by the member 47 is opened oil is allowed to flow between the jack 7 and the tank 6 to lower the platform 15 with or without a load thereon and also during raising of saidplatform 15 during operation of the quick-lift mechanism.

While according to the foregoing description relative to a preferred embodiment of this invention :the platform 15 has been raised quickly as desired by a combilever 46 is operated, it will be obvious that such control of the valve operated by the member 47 maybe eliminated by providing a check valve in the hydraulic circuit between the oil tank 6 and the jack 7. Moreover, the handle shaft 36 employed in the preferred embodiment of this invention as hereinbefore described to operate the pump 9 may be replaced with some other operating mechanism such as a wheel-shaped handle.

Thus, it will be quite apparent from the foregoing description that the present invention provides a very efficient lift carrier which is provided on its traction body 2 with both a jack 7 to be used to lift a heavy load, and a quick-lift mechanism to be used when the platform 15 carries no load or only a small load which does not require a large amount of force to lift, whereby the length of time and amount of labor required to raise the platform 15 can be drastically saved depending on the weight of the load carried on the platform l5.

It will be understood that various modifications or-alterations may be made by those skilled in the art to the apparatus as herein'described without departing from the scope and spirit of the present invention which are defined by the appended claims.

What is claimed is:

1. In a lift carrier having a platform and a traction body, said platform moveable in respect to said traction body, an improvement wherein said lift carrier includes a first lift device provided on said traction body for raisingand lowering-the front end portion of said platform; a device for operating said first lift device; a second lift device in the form of'a single stroke quick-lift mechanismprovided on the upper portion of said first lift deraised by said quick-lift mechanism.

.2. The invention as defined in claim 1, wherein'said first lift device comprises a fluid jack lift including a jack, and a tank for fluid, said tank being cylindrically shaped and surrounding said jack,'said jack lift including a handle shaft pivotally supported on said tank, said jack lift operative by stroking said handle's'haft to raise said jack to raise-said platform.

*3. In a lift carrier having a platform and a traction body, said platform moveable in respect'to said traction body, an improvement wherein said lift carrier includes afirst lift device provided on said traction body for raising and lowering the front end portion of said platform; a device for operatingsaid first lift device; a second lift device in the formof a single stroke quick-lift mechanism provided on the upper portion of said first lift device, said quick-lift mechanism operative alternately withsaid first lift device to raise said front end portion of said platform quickly; and a device provided on said lift operating device adapted to be engageable with said quick-lift mechanism for operating said quick-lift mechanism, said first lift device operative in conjunction with said quick-lift mechanism to hold'said platform in the elevated position to which it is quickly raised bysaid quick-lift mechanism, said first lift device comprising a fluid jack lift including a jack, and a tank for fluid, said tank being cylindrically shaped and surrounding said jack, said jack lift including a handle shaft pivotally supported on said tank, said jack lift operative by stroking said handle shaft to raise said jack to raise said platform, bell crank means pivotally supported on said tank so as to raise and lower said quicklift mechanism, and a manually actuable device on said handle shaft for engaging said bell crank means to raise and lower said quick-lift mechanism with a single stroke of said handle shaft.

4. The invention as defined in claim 3, wherein said quick-lift mechanism comprises a substantially channel shaped quick-lift yoke inserted over the plunger of said jack lift and adapted to be vertically slidable relative to said plunger and fluid tank; a bracket provided on said tank, the lower end of said handle shaft pivotally attached to said bracket; a pair of substantially L-shaped operating arms attached to said bracket pivotally about the axis of rotation of said handle shaft and adapted to abut against the lower edges of the depending side walls of said quick-lift yoke and move said yoke when they are rotated; and an engaging member connecting one of the legs of one of said operating arms and the corresponding leg of the other operating arm.

5. The invention as defined in claim 4, wherein said device for operating said quick-lift mechanism comprises a locking member pivotally attached to the lower end portion of said handle shaft and adapted to be engaged with said engaging member when said locking member is rotated, and an operating rod for rotating said locking member, said locking member being engaged with said engaging member upon actuation of said operating rod, whereupon said pair of operating arms are caused to rotate together with said handle shaft, and the legs of said operating arms other than those connected by said engaging member move said quick-lift yoke, whereby the front end of said platform is moved.

6. The invention as defined in claim 5, wherein said operating rod is housed within said handle shaft and is movable longitudinally of said handle shaft.

7. The invention as defined in claim 6, further including a valve for said jack lift and means for opening or closing said valve by moving said operating rod upward or downward.

8. The invention as defined in claim 3, further including means for maintaining said platform in a substantially horizontal position while said platform is being raised or lowered.

9. An improved lift carrier having a platform and a traction body, said platform moveable in respect to said traction body, a first lift means in the form of a fluid jack lift for lifting said platform in respect to said traction body under load including manually operated means, and a quick-lift mechanism operative alternately in respect to said first lift means for lifting said platform with no load or a small load, said first lift means operative by manually stroking said first manually operated means, said quick-lift mechanism operative with a single stroke of said manually operated means, said first lift means operative in conjunction with said quick-lift mechanism to hold said platform in the elevated position to which it is quickly raised by said quick-lift mechanism.

10. An improved lift carrier having a platform and a traction body, said platform moveable in respect to said traction body, a first lift means in the form of a fluid jack lift for lifting said platform in respect to said traction body under load including first manually operated means, and a quick-lift mechanism operative alternately in respect to said first lift means for lifting said platform with no load or a small load, said first lift means operative by manually stroking said first manually operated means, said quick-lift mechanism operative with a single stroke of said first manually operated means, said first lift means operative in conjunction with said quick-lift mechanism to hold said platform in the elevated position to which it is quickly raised by said quick-lift mechanism, said first lift means including a fluid pump, said first manually operated means having means for actuating said pump during manual stroking of said first manually operated means, valve means controlling flow of fluid to and from said jack lift, and second manually operated means for actuating said valve means, said valve means closed during raising of said platform by actuation of said pump by said first manually operated means, said second manually operated means operative to open said valve means during raising of said platform by actuation of said quick-lift mechanism and also to lower said platform.

11. An improved lift carrier as claimed in claim 10, third manually operated means operative alternately with said second manually operated means to open said valve means to lower said platform.

12. An improved lift carrier as claimed in claim 11, said second manually operated means a hand operated means, operated means a foot operated means.

13. An improved lift carrier as claimed in claim 10, means for latching said first manually operated means in respect to said quick-lift mechanism so that the latter is actuated by the former in a single stroke thereof, said latching means operated by said second manually operated means.

' insert between "means" and "operated" Q said third manually UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Pa ten t No r S1. i'll'f"! hlvefl tor 1; i l lg j '7 It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 7 '1'ine 39, delete "first". Column 8 line 36,

Signed and sealed this 1st day of 0ctober 1974.

(SEAL) Attest:

McCOY M. GIBSON JR. 0. MARSHALL 'DAN A x Attesting Officer Commissioner of Patents USCOMM-DC 60376-P69 u 5, GOVERNMENT PRINTING orncz: 930

"ORM PO-105O (10-69) 

1. In a lift carrier having a platform and a traction body, said platform moveable in respect to said traction body, an improvement wherein said lift carrier includes a first lift device provided on said traction body for raising and lowering the front end portion of said platform; a device for operating said first lift device; a second lift device in the form of a single stroke quick-lift mechanism provided on the upper portion of said first lift device, said quick-lift mechanism operative alternately with said first lift device to raise said front end portion of said platform quickly; and a device provided on said lift operating device adapted to be engageable with said quicklift mechanism for operating said quick-lift mechanism, said first lift device operative in conjunction with said quick-lift mechanism to hold said platform in the elevated position to which it is quickly raised by said quick-lift mechanism.
 2. The invention as defined in claim 1, wherein said first lift device comprises a fluid jack lift including a jack, and a tank for fluid, said tank being cylindrically shaped and surrounding said jack, said jack lift including a handle shaft pivotally supported on said tank, said jack lift operative by stroking said handle shaft to raise said jack to raise said platform.
 3. In a lift carrier having a platform and a traction body, said platform moveable in respect to said traction body, an improvement wherein said lift carrier includes a first lift Device provided on said traction body for raising and lowering the front end portion of said platform; a device for operating said first lift device; a second lift device in the form of a single stroke quick-lift mechanism provided on the upper portion of said first lift device, said quick-lift mechanism operative alternately with said first lift device to raise said front end portion of said platform quickly; and a device provided on said lift operating device adapted to be engageable with said quick-lift mechanism for operating said quick-lift mechanism, said first lift device operative in conjunction with said quick-lift mechanism to hold said platform in the elevated position to which it is quickly raised by said quick-lift mechanism, said first lift device comprising a fluid jack lift including a jack, and a tank for fluid, said tank being cylindrically shaped and surrounding said jack, said jack lift including a handle shaft pivotally supported on said tank, said jack lift operative by stroking said handle shaft to raise said jack to raise said platform, bell crank means pivotally supported on said tank so as to raise and lower said quick-lift mechanism, and a manually actuable device on said handle shaft for engaging said bell crank means to raise and lower said quick-lift mechanism with a single stroke of said handle shaft.
 4. The invention as defined in claim 3, wherein said quick-lift mechanism comprises a substantially channel shaped quick-lift yoke inserted over the plunger of said jack lift and adapted to be vertically slidable relative to said plunger and fluid tank; a bracket provided on said tank, the lower end of said handle shaft pivotally attached to said bracket; a pair of substantially L-shaped operating arms attached to said bracket pivotally about the axis of rotation of said handle shaft and adapted to abut against the lower edges of the depending side walls of said quick-lift yoke and move said yoke when they are rotated; and an engaging member connecting one of the legs of one of said operating arms and the corresponding leg of the other operating arm.
 5. The invention as defined in claim 4, wherein said device for operating said quick-lift mechanism comprises a locking member pivotally attached to the lower end portion of said handle shaft and adapted to be engaged with said engaging member when said locking member is rotated, and an operating rod for rotating said locking member, said locking member being engaged with said engaging member upon actuation of said operating rod, whereupon said pair of operating arms are caused to rotate together with said handle shaft, and the legs of said operating arms other than those connected by said engaging member move said quick-lift yoke, whereby the front end of said platform is moved.
 6. The invention as defined in claim 5, wherein said operating rod is housed within said handle shaft and is movable longitudinally of said handle shaft.
 7. The invention as defined in claim 6, further including a valve for said jack lift and means for opening or closing said valve by moving said operating rod upward or downward.
 8. The invention as defined in claim 3, further including means for maintaining said platform in a substantially horizontal position while said platform is being raised or lowered.
 9. An improved lift carrier having a platform and a traction body, said platform moveable in respect to said traction body, a first lift means in the form of a fluid jack lift for lifting said platform in respect to said traction body under load including manually operated means, and a quick-lift mechanism operative alternately in respect to said first lift means for lifting said platform with no load or a small load, said first lift means operative by manually stroking said first manually operated means, said quick-lift mechanism operative with a single stroke of said manually operated means, said first lift means operative in conjunction with said quick-lift mechanism to hold said platform in the elevated poSition to which it is quickly raised by said quick-lift mechanism.
 10. An improved lift carrier having a platform and a traction body, said platform moveable in respect to said traction body, a first lift means in the form of a fluid jack lift for lifting said platform in respect to said traction body under load including first manually operated means, and a quick-lift mechanism operative alternately in respect to said first lift means for lifting said platform with no load or a small load, said first lift means operative by manually stroking said first manually operated means, said quick-lift mechanism operative with a single stroke of said first manually operated means, said first lift means operative in conjunction with said quick-lift mechanism to hold said platform in the elevated position to which it is quickly raised by said quick-lift mechanism, said first lift means including a fluid pump, said first manually operated means having means for actuating said pump during manual stroking of said first manually operated means, valve means controlling flow of fluid to and from said jack lift, and second manually operated means for actuating said valve means, said valve means closed during raising of said platform by actuation of said pump by said first manually operated means, said second manually operated means operative to open said valve means during raising of said platform by actuation of said quick-lift mechanism and also to lower said platform.
 11. An improved lift carrier as claimed in claim 10, third manually operated means operative alternately with said second manually operated means to open said valve means to lower said platform.
 12. An improved lift carrier as claimed in claim 11, said second manually operated means a hand operated means, operated means a foot operated means.
 13. An improved lift carrier as claimed in claim 10, means for latching said first manually operated means in respect to said quick-lift mechanism so that the latter is actuated by the former in a single stroke thereof, said latching means operated by said second manually operated means. 